Chimney-cowl.



No. 888,728. PATENTBD MAY 26, 1908.

' D. MoLEAN.

CHIMNEY GOWL.

APPLICATION nnnn um. 19, 1907.

of i a INVENICOIR A TTOHNEYS.

rm: mam: PIPERS co.. wAsmunwlv-imc.

subject of the King of Great Britain, and re- DUNCAN MCLEAN, OF NORTH SHIELDS, ENGLAND.

CHIMNE Y-GOWL.

' Application filed August 19,

Specification of Letters Patent.

Patented May 26, 1908.

1907. Serial No. 389,120.

T 0 all whom it may concern:

Be it known that I, DUNCAN McLEAN, a

siding at North Shields, in the county of Northumberland, England, have invented certain new and useful Improvements in Chimney-Cowls, of which the following is a specification, such as will enable those skilled in the art to which it appertains to make and use the same. 7

This inventionrelates to what are known as chimney cowls and similar devices for improving the up draft and minimizing the down draft in chimneys, ventilating shafts and similar structures; and the object thereof is to provide an improved device of this class which is simple in construction and operation and comparatively inexpensive and which may be practically and successfully applied-wherever such devices are required.

My improved cowl apparatus or device comprises a swinging or pivoted canopy or casing adapted to inclose the top part of a chimney, flue, air shaft or the like and adapted to swing or tilt in any direction and provided with one or more flat rings or annular disks which are supported above the canopy or casing.

The invention is fully disclosed in the following specification, of which the accompanying drawing forms part, in which the separate parts of my improvei'nent are designated by suitable reference characters in each of the views, and in which;

Figure 1. is a side elevation showing the top part of a chimney or flue and one form of my improved. apparatus or device; Fig. 2 a central vertical section of the device as shown in Fig. 1; and, Fig. 3 a view similar to Fig. l but showing the device tilted as in the operation thereof.

Referring to the drawings, this form of my invention comprises a canopy or casing a of greater diameter than the chimney pot or line b and surrounding the upper part of same and extending below and above the top thereof. The canopy or casing is pivoted to the flue 7) by straps or cross-pieces c. d, and a bolt 6 or otherwise suitably attached thereto so that it is free to swing,pivot or tilt in any direction. Above the canopy or casing a I mount one or more concentric flat rings or annular disks supported from the canopy or casing by stays g, and preferably decreasing in diameter upwardly cone-fashion. The rings or I disks are preferably surmounted by a cap or cover it though in some cases the cap or cover may be dispensed. with.

In use, when there is no wind, the smoke issues from the top of the canopy or casing a and between the rings or disks Vfhen wind is blowing in a downward direction .rings or disks causes a suction up the pot or flue 1) thereby increasing the up draft in the chimney. If desired the upper edge of the canopy or casing a may be beveled or turned inward as shown in Fig. 2 to deflect wind striking it.

I have found by experiment that good re sults may sometimes be obtained by proportioning the apparatus so that the part above the pivot 6 offers a greater surface to the wind than the portion below the pivot or by weighting the apparatus, or by providing the upper portion with vanes ,or otherwise suitably arranging the apparatus so that the bottom end of the canopy or casing tilts towards the wind instead of to the leeward as above described. Thus, if wind is blowing in the direction of the arrow Y in Fig. 3 and the canopy or casing a is tilted as shown, part of the wind will be deflected up between the pot or flue Z) and the canopy or casing 11' and will considerably improve the up draft in the pot or flue I) while the rings or disks f will, as before, prevent the wind striking the outlet of the pot or flue b.

The precise proportions of the various parts will, of course, depend upon the particular circumstances in use, but I have obtained good results by making the pot or flue b of one-third lesser diameter than the canopy or casing a, the outer diameter of the lowermost ring or disk equal to twice the diameter of the pot or flue I), the inner diameter of said ring or disk slightly less than the diameter of the canopy or casing a and the successive rings or disks of corresponding less inner diameter until the inner diameter of the uppermost ring is equal to half the I diameter of the pot or flue Z) and arranging the rings or disks about one-fourth of the diameter of the pot or flue l) apart. The pot or flue b may stand over a single chimney flue or over two or more lines which may be gathered or groupedtogether for the purpose, and the pot or flue b may conveniently e equal in cross sectional area to about two-thirds of the cross-sectional area of the flue or flues over which it stands.

Apparatus as above described may be used in connection with ventilating shafts, and in such cases the flue b or the shaft may be pro vided with a suitable outlet for rain which may enter between. the rings or disks 1 am aware that it has been proposed. to

' provide a chimney pot or the like with a pivoted. canopy adapted to pivot or tilt in any direction and that it has also been proposed to provide a fixed or non-pivoting canopy with flat or conical rings but it has not hitherto been proposed to provide a pivoting cano- .py with flat rings as herein described.

Having fully described my invention, what I claim as new and desire to'se'cure by Let ters Patent, is

1, In a chimney or flue member, a casing open at the top and bottom and of greater diameter than the chimney or flue member and pivotally supported centrally of and above the chimney or flue member whereby said casing-is adaptedv to swing laterally, said. "casing being provided at the top thereof with upwardly and. inwardly directed stays, and a plurality of spaced annular plates connected at the top and bottom, means for pivotally supporting said casing centrally and above a flue member, a plurality of stays connected with the top of said casing and converging upwardly and a plurality of equally spaced annular plates connected with said stays and decreasing in diameter upwardly, the top of said stays being also provided with a cap.

3. The herein described means for improving the up drafts and minimizing the down drafts in chimneys, comprising a casing open at the top and. bottom, means for pivotally supporting said casing centrally and above a flue member, a plurality of stays connected with the top of said casing and (.onverging upwardly and a plurality of equally spaced annular plates connected with said stays and decreasing in diameter upwardly, the top of said stays being also provided with a cap,

and the top of said casing being provided with an inwardly directed annular flange.

In testimony that I claim the foregoing as my invention l. have signed my name in pres ence of the subscribing witnesses this seven th day of August 1907.

DUNCAN McLEAN.

Witnesses:

WILLIAM Henson NIXON, WILLIAM URE. 

